Barrier-limited surface modification of nanochannels via binding polymers

Surface modification of nanochannels via binding polymers is important in cutting-edge research disciplines such as the design of functional ion channels or ${\mathrm{CO}}_{2}$ capture and conversion. Capturing surface modifications of nanochannels remains a great challenge due to the barrier-limited binding kinetics of polymers on the inner surfaces of nanochannels. By using our newly developed integral of first passage times (IFS), we show that the barrier-limited surface modifications of nanochannels highly depend on the bending magnitudes of inner surfaces. The highly curved surfaces can absorb less polymers than those on the weakly curved surface. In particular, we show that the final polymer densities on the inner surfaces of nanochannels and nanospheres are closer to each other at the same radius but with different mean curvatures. The findings clarify that the protracted surface modifications of the nanochannels are primarily dictated by the channel radius, providing useful guidelines for designing functional nanochannels in different applications.